Lubricant composition



Patented Aug. 5, 1947 2,425,174 \LUBBIOANT COMPOSITION Emmett S. Carmichael, Jackson Heights, and

Theodore G. lloehner, Malvcrne, N. Y., asslgnors to Socom-Vacuum Oil Company. Incorporated, New York, N. Y., a corporation of New York No Drawing. Application July 31, 1941,

I SeriaiNo. 404,840

8 Claims. (Cl. 252-33) This invention relates to a lubricant for cold rolling of steel, particularly thin gauge metal such as that destined for tin plate.

Soluble oil emulsions have long been used for rolling steel where reductions to gauge were small and where the surface structure of the metal was not as important as for tin plate. Aqueous roll lubricants for this application have been emulsions of the il-in-water type, and their principal value has been as coolants. Experience has shown that emulsions of the oil-in-water type remain completely ineffective as lubricants for rolling tin plate for a period of 36 to 48 hours, and only after such break in period begin to show a lubricating value. spoilage and loss of steel during this break in period is large, the rate of production is low, and general dissatisfaction exists among the rollers in the mills because of the adverse effeet on the equipment and production.

As an example of such commercially used roll lubricants we give the following:

Per cent Palm oil 50 Mineral soluble oil 50 We have made the discovery that if a roll lubricant capable of forming an oil-in-water emulsion is treated with asmall amount of mineral salt of metals or any other bases inorganic or organic, capable of reversing the phases of the emulsion, the resulting compound emulsion is suitable for immediate application without any undesirable "breaking in" period. While the mechanism of the lubrication is not exactly known, it is the belief of the inventors that the success of their discovery can be attributed to the fact that a compound emulsion is formed. By that is meant that a water-in-oil emulsion of the roll lubricant is dispersed in the balance of the water thus forming three phases: water- 1- water.

As an example of roll lubricant representative of this invention, we give the following:

Example I Palm oil per cent by weight 4.9 Mineral soluble oil s ..do 4.9 Magnesium sulfate per cent .2 Water do 90.0

The procedure for the preparation of the emulsified roll lubricant is as follows: Equal parts of palm oil and mineral soluble oil are mixed with almost the total quantity of Water. Unless the palm oil contains excessive quantities of free fatty acids, an oil-in-water emulsion is easily formed. To that emulsion the solution of magnesium sulfate in the balance of the water, as shown in the formula, is added, thus forming the compound emulsion.

An excess of free fatty acids in the palm oil may revent the emulsification of the mixture of palm oil and solubleoil. In this case the soluble oil is first emulsified with almost the total amount of water; then the palm oil is added gradually with agitation and finally the solution of magnesium sulfate is stirred in.

The characterizing ingredents of the presently discussed composition are a soluble oil capable of forming an oil-in-water emulsion, and an emulsion inverting material, so handled as to form a three phase dispersion system in which an oilexternal-water-internal dispersion is itself dispersed to form the internal phase in an aqueous emulsion.

The oleaginous or soluble oil material is composed of an oil or oil mixture and an emulsifier capable of forming an oil-in-water emulsion. The oily material may be wholly mineral oil, although such compositions are relatively less effectual, but is preferably composed substantially of a vegetable or animal oil or fat, such as palm oil, cocoanut oil, cottonseed oil, wool fat, lard oil, tallow, fish oil, hydrogenated fatty oils, and the like.

The emulsifier capable of forming oil-in-water emulsions, which is compounded with the oily material to form a soluble oil may be any of the usual emulsifiers so used. A very' typical and usual material of this type is an alkali soap of a mineral oil sulphonate, with or without assistant emulsifying agents. The emulsifier mixture of the example designated herein as mineral soluble oil" was a mixture of oil, the sodium soaps of if i mineral oil sulphonates, and potassium salts of the fatty acids frequently designated as tall oil and derived from sulphite paper pulp mill waste. Numerous other common emulsifying agents may be so used such as alkali soaps of rosin, oleic acid, naphthenic acids, etc.

The emulsion inverter material may be any one 'of those numerous salts of bivalent or polyvalent metals or organic bases which are capable of inverting oil-in-water emulsions to form water-inoil emulsions. Magnesium sulphate is a cheap and eifective material which commonly is so used. Other such materials are calcium chloride, zinc chloride, lead chloride, the chlorides of iron, aluminum sulfate, diglycol stearate, glycol oleate. etc.

It will be remembered that the lubricating composition has been described as a water-in-oil-in inverter to be used in any given formulation is' dependent upon such factors as the quantity and nature of the soaps used, the free acidity, etc. Consequently the amount must be determined by experiment, in the usual manner, 'with each formulation. For the particular formulation given in Example I above, using magnesium sulphate as inverter, the amount of inverter should be less than 0.5% and preferably between 0.1% and 0.3%.

We claim:

- 1. A lubricant for use in the cold rolling of steel comprising an emulsion wherein water is the continuous phase and the disperse phase is a waterin-oil emulsion, said composition bein constituted of water, a lubricating oleaginous material, an emulsifier capable of emulsifying the oleaginous material in water, and sufficient amount of a salt of a polyvalent metal to bring about the formation of an emulsion of the compound type.

2. A lubricant composition comprising a lubricating oleaginous material selected from the group consisting of mineral oils, animal oils and vegetable oils and mixtures thereof, a surface active material to emulsify the oleaginous mate: rial in water, water, and a material selected from the group consistin of salts of polyvalent metals capable of causing phase inversion of the first formed emulsion, the water, lubricant, emulsifier, and inverter being present in such proportions as to give a stable water-continuous emulsion the oil droplets of which are themselves a water-inoil emulsion.

3. A lubricant for cold rolling metal comprising a lubricating .oleaginous material selected from the group mineral oils, animal oils, vegetable oils, and mixtures thereof, which oleaginous material is dispersed as the internal phase of an oil-in-water emulsion, and which itself is the external phase of a water-in-oil emulsion, an emulsifier capable of emulsifying said oleaginous material in water, and a phase inverter selected from the group consisting of esters of polyvalent organic bases capable of inverting oil-in-water emulsions, the water, lubricant, emulsifier, and

inverter bein present in such proportions as to give a stable water-continuous emulsion the oil droplets of which are themselves a water-in-oil emulsion.

4. A lubricant composition comprising water, a lubricating oleaginous material selected from the group consisting of mineral oils, animal oils. vegetable oils and mixtures thereof, a surface active material selected from the group consisting of alkali soaps of rosin, oleic acid, sulphonic acids, naphthenlc acids, and heavy fatty acids, and a phase inverter selected from the group consisting of magnesium sulphate, calcium chloride, lead chloride, zinc chloride, iron chlorides, aluminum sulphate; the emulsifier and phase inverter being so proportioned as to give rise to water-in-oil emulsion particles dispersed in a continuous water'phase.

5. A method of lubricating steel subjected to gauge reduction in cold rolling by applying to the steel being rolled a lubricant comprising an emulsion wherein water is the continuous phase and the disperse phase is a water-ln-oil emulsion, said composition being constituted of water, a lubricating oleaginous material, an emulsifier capable of emulsifying theoleaginous material in water, and a sufficient amount of an emulsion inverter, to effect th formation of an emulsion of the compound type.

6. A method of lubricating steel subjected to gauge reduction in cold rolling by applying to the steel being rolled a lubricant comprising a lubricating oleaginous material selected from the group consisting of mineral oil, animal oils and vegetable oils and mixtures thereof, a surface active material to emulsify the oleaginous material in water, water, and a material selected from the group consisting of salts of polyvalent metals capable of causing phase inversion of the first formed emulson, the water, lubricant, emulsifier, and inverter being present in such proportions as to give a stable water-continuous emulsion the oil droplets of which are themselves a water-in-oil emulsion.

'7. A method of lubricating steel subjected to gauge reduction in cold rolling by applying to the steel being rolled a lubricant comprising a lubricating oleaginous material selected from the group mineral oils, animal oils, vegetable oils, and mixtures thereof, which oleaginous material is dispersed as the internal phase of an oil-inwater emulsion, and which itself is the external phase of a water-in-oil emulsion, an emulsifier capable of emulsifying said oleaginous material in water, and a phase inverter selected from the group consisting of esters of polyvalent organic bases capable of inverting oil-in-water emulsions, the water, lubricant, emulsifier, and inverter being present in such proportions as to give a stable water-continuous emulsion the oil droplets of which are themselves a water-in-oil emulsion.

8. A method of lubricating steel subjected to gauge reduction in cold rolling by applying to the steel being rolled a lubricant comprising water, a lubricating oleaginous material selected from the group consisting of mineral oils, animal oils, vegetable oils and mixtures thereof, a surface active material selected from the group consisting of alkali soaps of rosin, oleic acid, sulphonic acids, naphthenic acids, and heavy fatty acids, and a phase inverter selected from the group consisting of magnesium sulphate, calcium chloride, lead chloride, zinc chloride, iron chlorides, aluminum sulphate; the emulsifier and phase inverter being so proportioned as to give Number Name Date rise to water-in-oil emulsion particles dispersed 2,231,214 Nelson Feb. 11, 1941 in a continuous water phase. 2,307,744 Liberthson Jan. 12, 1943 2,303,142 Spangier Nov. 24, 1942 EMMETT S. CARMICHAEL. 5 2,230,556 Zimmer Feb. 4, 1941 THEODORE G. ROEHNER. 1 2,214,634 7 Dombrow Sept. 10, 1940 REFERENCES CITED 1,724,653 Hertman Aug. 13, 1939 The following references are of record in the REFERENCES file of this patent: l0 Phase Volume Theory and the Homogenization of Concentrated Emulsions, part II, by Parke, in

n UNITED STATES PATENTS Journaliof the Chemical Societ of London, pages Number 7 Name Date 1112-1115,,pt-2, July-Dec.1934 Proceed.

2,071,488 Zimmer Feb. 23, 1937 Studies inEmuisions, by Seifriz. in Journal of 2,152,396 Williams ,Mar. 23, 1939 15 Physical Chemistry, vol. 29, 1925, pages 738-749. 

